After planting in a favorable, prepared soil, the numerous eyes that appear on the underground stem of the banana tree evolve into shoots, composed of long leaves. On selected shoots, the leaves overlap to form a false trunk between 1.5 and 8 m in length depending on the species of banana tree and culturing conditions.
After blooming, the bracts fall off one after another revealing the fruits or fingers which at that point hang downward. In the following months these fingers rise, curve, lengthen, and enlarge, forming hands connected to the stem of the banana bunch.
After the bunch has been picked, the false trunks are cut down because they can only blossom thereafter.
This operation marks the end of one production cycle and starts the next cycle.
During the last phase of the production cycle, several young shoots are selected from each stem by cutting. They ensure continuation of the crop.
In mechanizable plantations, for economic reasons linked to various factors, after a variable period of time the banana trees have to be destroyed and the land left fallow or replanted. The best plants are then selected and removed from the parcel to be replanted after preparation of the soil.
At the present time this soil preparation consists of chopping up the false trunks and other plant debris and burying them in the soil by means of heavy disk choppers that have to make four or five intersecting passes over the land to arrive at average results because the false trunks are difficult to chop and do not break down easily once they are in the soil.
The use of such machines compacts the soil because of weather conditions. Particularly with heavy rainfall, the soil is often very wet.
Moreover the water content of the debris, which is very high--on the order of 90%--associated with the quantity of debris buried, approximately 200 tons per hectare, creates a great deal of water which, added to the natural wetness of the soil, interferes with the later subsoiling operation rendered necessary by the compacting brought about by the disk choppers.
This subsoiling operation, performed by decompacting tools in several intersecting passes, rarely brings about the desired splitting and breakup of the compact areas, which breakup loosens up the soil, because when the teeth of the tools penetrate very wet soil they cause no breakup whatever.
Because of the above, present-day soil preparation techniques are unsatisfactory in terms of the quality of debris chopping and subsequent debris destruction as the means employed alter the structure of the soil, requiring additional steps of uncertain effectiveness.